The BBImpulse indicator is based on the standard Moving Average indicator.

You have MA input parameters:

• maPeriod - Moving Average period;
  
• maMODE - Moving Average mode (0 = MODE_SMA; 1 = MODE_EMA; 2 = MODE_SMMA; 3 = MODE_LWMA);
• maPRICE - Applied price (0=PRICE_CLOSE; 1=PRICE_OPEN; 2=PRICE_HIGH; 3=PRICE_LOW; 4=PRICE_MEDIAN; 5=PRICE_TYPICAL; 6=PRICE_WEIGHTED).

Green Histogram is representing an UP-trend, Red Histogram is representing a Down-trend.